The transformation view and the flow view are two major conceptualizations of production. The current practice in construction is based on the transformation view. However, the transformation view is an idealization, and in a complex production situation the associated idealization error may become large. This is exactly what happens in practice. Task management, based on the transformation view, assumes that certainty prevails in production. However, it is widely observed that, due to the inherent variability of production in construction, intended task management degenerates into mutual adjustment by teams on site. It is argued that the transformation view and the flow view should be synthesized into a new theoretical view on construction. The inherent causes of variability in construction can be explained and the countermeasures for eliminating variability or stemming its impact can be pinpointed by this new theoretical view. It is shown that the Last Planner method is compatible with this new view
